A review of biomolecules conjugated lanthanide up-conversion nanoparticles-based fluorescence probes in food safety and quality monitoring applications.

Upconversion nanoparticles (UCNPs) are known to possess unique characteristics, which allow them to overcome a number of issues that plague traditional fluorescence probes. UCNPs have been employed in a variety of applications, but it is arguably in the realm of optical sensors where they have shown the most promise. Biomolecule conjugated UCNPs-based fluorescence probes have been developed to detect and quantify a wide range of analytes, from metal ions to biomolecules, with great specificity and sensitivity. In this review, we have given much emphasis on the recent trends and progress in the preparation strategies of bioconjugated UCNPs and their potential application as fluorescence sensors in the trace level detection of food industry-based toxicants and adulterants. The paper discusses the preparation and functionalisation strategies of commonly used biomolecules over the surface of UCNPs. The use of different sensing strategies namely heterogenous and homogenous assays, underlying fluorescence mechanisms in the detection process of food adulterants are summarized in detail. This review might set a precedent for future multidisciplinary research including the development of novel biomolecules conjugated UCNPs for potential applications in food science and technology.

Recent developments in Polyhydroxyalkanoates (PHAs) production - A review.

Polyhydroxyalkanoates (PHAs) are inevitably a key biopolymer that has the potential to replace the conventional petrochemical based plastics that pose jeopardy to the environment globally. Even then the reach of PHA in the common market is so restricted. The economy of PHA is such that, even after several attempts the overall production cost seems to be high and this very factor surpasses PHAs usage when compared to the conventional polymers. The major focus of the review relies on the synthesis of PHA from Mixed Microbial Cultures (MMCs), through a 3-stage process most probably utilizing feedstocks from waste streams or models that mimic them. Emphasis was given to the works carried out in the past decade and their coherence with each and every individual criteria (Aeration, Substrate and bioprocess parameters) such that to understand their effect in enhancing the overall production of PHA.

Bioinspired morphology-controlled silver nanoparticles for antimicrobial application.

Phytochemicals sources have been extensively used as reducing and capping agents for synthesis of nanoparticles (NPs). However, morphology-controlled synthesis and shape/size dependent applications of these NPs still need to be explored further, and there is a need to develop a way in which particular and optimized phytochemicals result in the desired NPs in lesser time and cost with higher reproducibility rate. The present study is focused on morphology-controlled synthesis and shape/size dependent application of silver NPs based on the fractionated phytochemicals of Elaeagnus umbellata extract (EU). Unlike other approaches, in this study the reaction parameters such as time, temperature, pH, stirring speed and concentration of the precursor solutions were not altered during the optimization process. The fractionated phytochemicals were used separately for the synthesis of AgNPs, and the synthesized NPs were characterized by UV-visible, FT-IR, atomic force microscopy (AFM) and scanning electron microscopy (SEM). Our findings suggested that the constituents of the extract fractions varied with the selection of the extraction solvent, and the shape/size, bactericidal properties and toxicity of the NPs have a strong correlation with the phytochemicals of the plant extract. The fractionated phytochemicals present in the water fractions (EUW) resulted in monodispersed spherical AgNPs in the size about 40 nm. The NPs have significant stability in physiological conditions (i.e. temperature, pH and salt), have good antibacterial activity, and were found to be non-toxic. Furthermore, AFM and SEM analysis exposed that the NPs killed the bacteria by disturbing the cellular morphology and releasing the cellular matrix. Our results justify the use of different fractions of plant extract to obtain detail implications on shape, size, antibacterial potential and toxicity of AgNPs. This is the first step in a controllable, easy and cheap approach for the synthesis of highly stable, uniform, non-toxic and bactericidal AgNPs using five fractions of EU. The findings suggested that the synthesized NPs, particularly from EUW, could be used in pharmaceutical and homeopathic industry for the development of antibacterial medications.

Discarded biodiesel waste-derived lignocellulosic biomass as effective biosorbent for removal of sulfamethoxazole drug.

This work aims to evaluate the removal of pharmaceutical drug using discarded biodiesel waste-derived lignocellulosic-based activated carbon biomaterial. Lignocellulosic-based activated carbon (LAC) biomaterial was prepared from Jatropha shell (biodiesel processing waste) by a zinc chloride activation method. The LAC biomaterial was characterized using various techniques including powder XRD, FT-IR, SEM-EDAX, and BET analysis. LAC biomaterial was applied to examine the adsorption of sulfamethoxazole (SMZ) drug in aqueous solution under ambient temperature. Various experimental parameters such as the effect of pH, treatment time, adsorbate concentration, and LAC dose of adsorption experiments were thoroughly examined and optimized. Under the optimal conditions, LAC biomaterial showed the maximum adsorption removal efficiency of SMZ drug. The kinetic models of Lagergren first-order, pseudo-second-order, intraparticle diffusion, and Bhangam's equation for SMZ removal onto LAC were used to recognize the probable mechanism of adsorption manner. From the experimental results, the Freundlich isotherm model (Kf = 83.56 mg g-1 (L mg-1)1/n) shows similar fit than the Langmuir (Q0 = 206.2 mg g-1) and Dubinin-Radushkevich (Qm = 150.69 mg g-1) condition models of adsorption isotherms. The rate constants of adsorption were found to confirm the pseudo-first-order kinetic and Bhangam's models with a significant correlation. The separation factor (RL) showed the favorable condition of the adsorption isotherm for the experimental system. The desorption results indicate that the ionic molecular exchange of SMZ from the hydroxyl group of LAC surface plays an important role in the recycling processes. Therefore, these results proved that the prepared low-cost LAC biomaterial could be used as an efficient adsorption material for the effective removal of pharmaceutical drugs in aqueous samples.

Bioprocess optimization and production of biosurfactant from an unexplored substrate: Parthenium hysterophorus.

Biosurfactants are one among the best alternative for synthetic surfactants that are exploited by many researchers. Several agro wastes help to reduce the cost biosurfactants by being renewable and economical. The present research focuses on the biosurfactant production from Pseudomonas mosselii utilizing Parthenium hysterophorus as a relatively cheap substrate. P. hysterophorus being a hazardous weed, its eradication is quite tedious. So, the utilization of the weed for useful purposes serves as a choice to overcome the problems posed by the weed. In the study, this weed has been successfully utilized as a substrate and the optimized fermentative production of biosurfactant was done. From one-factor-at a-time analysis it was known that the substrate level of 3% incubation time of 96 h, pH 6.0, temperature 35 °C, glucose and yeast extract was found to be the best C and N sources for a high yield. The extracted biosurfactant was partially purified and characterized using FTIR. The biosurfactant produced from the weed could help to render the milestone for distinct biomedical and other applications.

Polyhydroxyalkanoate production from statistically optimized media using rice mill effluent as sustainable substrate with an analysis on the biopolymer's degradation potential.

The present study focuses on the optimization of the bioprocess for the fermentative production of polyhydroxyalkanoate (PHA) by Acinetobacter junii BP 25 using rice mill effluent as a cheap substrate, henceforth to develop an economically feasible biopolymer production process. Statistical tools like Plackett-Burman design (PBD) and Response Surface Methodology (RSM) were used to evaluate the important variables that influence the yield of PHA. Initially from PBD three factors (glycerol, KH2PO4 and incubation time) were taken for further optimization using Box-Behnken design where, the interaction between each of the factors were studied in detail, providing a final optimized media for the high concentration of PHA. Before the optimization process the concentration of PHA was 0.52 ±â€¯0.05 g/l for 1.07 ±â€¯0.32 g/l cell dry mass (CDM) after which a 5.84 fold increase in PHA concentration was observed with 3.04 g/l of PHA. Biodegradation studies of the produced PHA sheets were investigated briefly in both terrestrial and aquatic ecosystem, showing degradation within 8 weeks in soil and 4 weeks in water which was very promising, as the non-degrading property of the conventional plastic have made scientist to research on biopolymers mainly.

Anthelmintic efficacy of glycolipid biosurfactant produced by Pseudomonas plecoglossicida: an insight from mutant and transgenic forms of Caenorhabditis elegans.

The current research focuses on the production and characterization of glycolipid biosurfactant (GB) from Pseudomonas plecoglossicida and its anthelmintic activity against Caenorhabditis elegans. The GB was purified and characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography and Mass Spectrometry (GC-MS) analysis. Anthelmintic activity of GB was studied at six different pharmacological doses from 10 to 320 µg/mL on C. elegans. Exposure of different developmental stages (L1, L2, L3, L4 and adult) of C. elegans to the GB reduced the survivability of worms in a dose and time-dependent manner. Adult and L4 worms were least susceptible, while L1, L2 and L3 were more susceptible to GB when compared to the untreated control. An increased exposure period drastically reduced the survival rate of worms and reduction in LC50 value. The GB significantly inhibited the development of C. elegans with an IC50 value of 53.14 µg/mL and even reduced the adult body length and egg hatching. Fecundity rate of the worms treated with GB at 20, 40 and 80 µg/mL decreased from 261.90 ± 3.21 to 239.70 ± 5.58, 164.20 ± 5.94 and 44.80 ± 6.22 eggs per worm, respectively. Besides the toxicological effects, prolonged exposure to GB significantly decreased (p ≤ 0.0001) the lifespan of wild type worms under standard laboratory conditions. Additionally, GB was found to be lethal towards ivermectin and albendazole resistant C. elegans strains. Overall, the data indicated that the GB extracted from P. plecoglossicida could be utilized for the control of non-susceptible and resistant gastrointestinal nematodes towards broad spectrum anthelmintic drugs, ivermectin and albendazole.

Bioprocess optimization of PHB homopolymer and copolymer P3 (HB-co-HV) by Acinetobacter junii BP25 utilizing rice mill effluent as sustainable substrate.

The potential use of parboiled rice mill effluent as a cheap substrate for the production of homopolymer and copolymer of Polyhydroxyalkanoates (PHAs) by Acinetobacter junii BP 25 was investigated for the first time. Process optimization by one factor at a time led to homopolymer polyhydroxybutyrate (PHB) production of 2.64 ± 0.18 g/l with 94.28% PHB content using a two-stage batch cultivation mode. BP 25 furthermore produced polyhydroxybutyrate-co-hydroxyvalerate (P3 (HB-co-HV)), with the addition of valeric acid as an additive to the substrate, yielding (2.56 ± 0.12 g/l dry biomass, 2.20 ± 0.15 g/l PHA) a copolymer content of 85.93%. Thus, rice mill effluent can be an effective and relatively low-cost alternative for the production of PHA, replacing the pure substrates.